The elaboration likelihood model (ELM) of persuasion[1] is a model of how attitudes are formed and changed (see also attitude change). Central to this model is the elaboration continuum, which ranges from low elaboration (low thought) to high elaboration (high thought). Depending on the extent of elaboration, different processes can mediate persuasion.

Contents

Key elements

The ELM distinguishes between two routes to persuasion: the central route and the peripheral route. Central route processes are those that require a great deal of thought, and therefore are likely to predominate under conditions that promote high elaboration. Central route processes involve careful scrutiny of a persuasive communication (e.g., a speech, an advertisement, etc.) to determine the merits of the arguments. Under these conditions, a person’s unique cognitive responses to the message determine the persuasive outcome (i.e., the direction and magnitude of attitude change).

Central route

Central route processes require a great deal of thought, and therefore are likely to predominate under conditions that promote high elaboration. Central route processes involve careful scrutiny of a persuasive communication (e.g., a speech, an advertisement, etc.) to determine the merits of the arguments. Under these conditions, a person's unique cognitive responses to the message determine the persuasive outcome (i.e., the direction and magnitude of attitude change). So, if favorable thoughts are a result of the elaboration process, the message will most likely be accepted (i.e., an attitude congruent with the message's position will emerge), and if unfavorable thoughts are generated while considering the merits of presented arguments, the message will most likely be rejected.[1] In order for the message to be centrally processed, a person must have the ability and motivation to do so.
Motivation and ability lead into the type of cognitive process that arise. This is favorbility, and favorbility is a positive or negative attitude change.

Peripheral route

Peripheral route processes, on the other hand, does not involve elaboration of the message through extensive cognitive processing of the merits of the actual argument presented. These processes often rely on environmental characteristics of the message, like the perceived credibility of the source, quality of the way in which it is presented, the attractiveness of the source, or the catchy slogan that contains the message.[1] The peripheral route is a mental shortcut process that accepts or rejects a message based on irrelevant cues as opposed to actively thinking about the issue [2]
The peripheral route is a process in which outside influences affect the decision making process. The most common influences would be factors such as reward. Reward could be objects like food, sex or money. These inducements create a quick change in mind. Likability is an influence along with expertise in the peripheral process. Appearance has the ability to gain the attention of individuals which can create interest. Celebrity status is another factor in which the peripheral process has become more popular. Humor within messages is a dominant influence in this process as well.
The goal of the peripheral process is to create change, this change can be weak change and even temporary change.

Central route vs. Peripheral route

Petty & Cacioppo suggest that you can only take one route in the act of persuasion (central route or peripheral route). What wasn’t recognized in their theory is the act of the peripheral route only gaining the attention of its receivers. For example if a persuader grasp the attention of the audience through peripheral factors such as humor and appearance but fails to have any knowledge of the message after that point, then the persuader will not create any change in the minds of the audience. This theory can act in a boomerang affect. Yes, it is possible for a persuader to gain the attention of the audience taking the peripheral route but question could cause the persuader to go back to the central route. This method is used in Advertisement all the time. An example of this would be a dating commercial that shows a group of attractive women that you could possibly date by just dialing the number that appears on the screen. Yes, it may grasp your attention but what happens when you want to know more about why this is the best approach for me finding someone to date? Petty & Cacioppo believe that you can only achieve persuasion through one of the routes, but under certain circumstances one route may not be enough.

Choice of route

The two factors that most influence which route an individual will take in a persuasive situation are motivation (strong desire to process the message; e.g., Petty & Cacioppo, 1979) and ability (actually being capable of critical evaluation; e.g., Petty, Wells, & Brock, 1976). Which route is taken is determined by the extent of elaboration. Both motivational and ability factors determine elaboration. Motivational factors include (among others) the personal relevance of the message topic, accountability, and a person's "need for cognition" (their innate desire to enjoy thinking). Ability factors include the availability of cognitive resources (e.g., the presence or absence of time pressures or distractions) or relevant knowledge needed to carefully scrutinize the arguments.The ability to understand the message that is being communicated. Distractions such as noise can affect the ability for one to process a message. An example of noise would be a persuader trying to share his message in a room full of crying babies, this would make it extremely difficult for listeners to concentrate on the message being given. Noise that you can't physically control would be if a persuaders listeners could concentrate on the message because they had something else on their mind which was more important than the persuaders message like a death in the family, or problems they're having in their relationship. The subject's general education level, as well as their education and experience with the topic at hand greatly affect their ability to be persuaded. Under conditions of moderate elaboration, a mixture of central and peripheral route processes will guide information processing.

Type of Elaboration: Objective Versus Biased Thinking

Attitude, motivation, and ability strongly increase the likelihood that a message will be ingrained in the minds' of listeners. Although, as the social judgement theory suggests, they may not process the information in a fair, objective way. Attitudes are general evaluations that people hold that correspond with how they perceive themselves in relation to the world they live in. Many of the evaluations are based on Cognitive intelligence, behavior, and guidance. Given a basic understanding of an individuals attitudes one can interpret which type of elaboration would better suit the situation. There are two types of elaboration a listener can possess: (Biased elaboration, Objective elaboration)
Elaboration can lead to both positive and negative results depending on the audience who is receiving the message. Individuals who have a Pre conception of a certain topic are going to be much harder to persuade oppose to an individual who has an open mind about a topic where only the facts hold truth.

Biased Elaboration: Top-down thinking in which predetermined conclusions color the supporting data.
Ex. Someone who has had a negative personal experience with motorcycles will probably have made up their minds and be biased in the way they process the message.[3]

Objective Elaboration: Bottom-up thinking in which facts are scrutinized without bias; seeking truth wherever it might lead. These listeners let the facts speak for themselves.
Ex. A person who is listening to a motorcycle salesman and already has a mindset about them. This person would let the facts influence their attitude.[3]

Testing the Elaboration Likelihood Model

To design a way to test the Elaboration Likelihood Model, it is crucial to determine whether an argument is universally seen as strong or weak. If an argument is inconsistent in opinions of strength, the results of persuasion will be inconsistent. In general, a weak argument that is universally viewed as weak will entice unfavorable results if the subject is instructed to and is in an appropriate environment to consider it logically (or when testing the central route of the Elaboration Likelihood Model). In turn, a strong argument under similar circumstances will return favorable results. The test arguments must also be rated for ease of understanding, complexity, and familiarity. To scientifically study either route of the Elaboration Likelihood Model, the arguments themselves must be designed to have consistent results.[4]

Conclusions of the Elaboration Likelihood Model

In addition to these factors, the ELM also makes several unique proposals.[1]

It is suggested that attitudes formed under high elaboration, the central route, are stronger than those formed under low elaboration. This means that this level of persuasion is stable over time and is less susceptible to decay or any type of counter-persuasion. Attitudes formed under low elaboration, the peripheral route, are more likely to cause a short term attitude change.

Variables in ELM routes can serve multiple roles in a persuasive setting depending on other contextual factors (examples below). Under high elaboration, a given variable (e.g., source expertise) can either serve as an argument ("If Einstein agrees with the theory of relativity, then this is a strong reason for me to as well") or as a biasing factor ("if an expert agrees with this position it is probably good, so let me see what else agrees with this conclusion" -- at the expense of information that may disagree with it).[5]

Under conditions of low elaboration, a given variable can act as a peripheral cue. This could happen, e.g., through the use of an "experts are always right" heuristic. Note that, while this is similar to the Einstein example presented above, this is a simple shortcut, which, unlike the Einstein example, does not require careful thought. Under conditions of moderate elaboration, a given variable can serve to direct the extent of information processing: "If an expert agrees with this position, I should really listen to what (s)he has to say".

Interestingly, when a variable affects elaboration, this can increase or decrease persuasion, depending on the strength of the arguments presented. If the arguments are strong, enhancing elaboration will enhance persuasion. If the arguments are weak, however, more thought will undermine persuasion.

More recent adaptations of the ELM (e.g.)[6] have added an additional role that variables can serve. They can affect the extent to which a person has confidence in, and thus trusts, their own thoughts in response to a message (self-validation role). Keeping with our source expertise example, a person may feel that "if an expert presented this information, it is probably correct, and thus I can trust that my reactions to it are informative with respect to my attitude". Note that this role, because of its metacognitive nature, only occurs under conditions that promote high elaboration.

Additional propositions

In addition to these factors, the ELM also makes several unique proposals.

Attitudes formed under high elaboration are stronger (more predictive of behavior and information processing, more stable over time, more resistant to persuasion) than those formed under low elaboration.

Variables can serve multiple roles in a persuasive setting depending on other contextual factors (examples below).

Under high elaboration, a given variable (e.g., source expertise) can either serve as an argument (“If Einstein agrees with the theory of relativity, then this is a strong reason for me to as well”) or as a biasing factor (“if an expert agrees with this position it is probably good, so let me see what else agrees with this conclusion” (at the expense of information that disagrees with it)).

Under conditions of low elaboration, a given variable can act as a cue (e.g., through the use of an “experts are always right” heuristic – note that while this is similar to the case presented above, this is a simple shortcut, and does not require the careful thought as in the Einstein example above).

Under conditions of moderate elaboration, a given variable can serve to direct the extent of information processing (“Well, if an expert agrees with this position, I should really listen to what (s)he has to say”). Interestingly, when a variable affects elaboration, this can increase or decrease persuasion, depending on the strength of the arguments presented. If the arguments are strong, enhancing elaboration will enhance persuasion. If the arguments are weak, however, more thought will undermine persuasion.

More recent adaptations of the ELM (e.g., Petty, Briñol, & Tormala, 2002) have added an additional role that variables can serve. They can affect the extent to which a person has confidence in, and thus trusts, their own thoughts in response to a message. Keeping with our source expertise example, a person may feel that “if an expert presented this information, it is probably correct, and thus I can trust that my reactions to it are informative with respect to my attitude”. Note that this role, because of its metacognitive nature, only occurs under conditions that promote high elaboration.

Application of the Elaboration Likelihood Model to HIV Prevention

A study performed in 1999 analyzed the effects of different persuasion techniques when trying to raise awareness of HIV prevention in an adolescent population. 298 eighth grade students were included in the study. Prior to the study, the students were categorized as being "information-oriented," "normative-oriented," or "diffuse-oriented" (defensive toward new ideas). The students were randomly assigned to listen to one of four audio messages that ranged from a strong argument, an HIV-infected teenager narrator, to a weak argument, a concerned parent. Upon analyzing their responses to the audio tape and a survey completed after, the "information-oriented" students had a stronger chance at attitude change than the other students. It was concluded that HIV prevention persuasion has much progress to make and that the information must be presented in a way that will reach all types of individuals. In this study, the Elaboration Likelihood Model was being tested for a particular use, and resulted in being effective but underdeveloped for this case.[7]